1. Field of the Invention
This invention pertains in general to recording multimedia content and pertains in particular to digital video recorders for recording and playing back video.
2. Background Art
Modern multimedia recording devices, such as video cassette recorders (VCRs) and digital video recorders (DVRs), often contain electronic program guides (EPG) that consumers utilize to specify programs to record. For example, a DVR may connect to a central server and download an EPG listing the starting and ending times of all programs carried by all channels received by that DVR in the next week. Typically, the central server also synchronizes a clock in the DVR. A user then utilizes the EPG to select the programs for the DVR to record. When the clock indicates that a specified program is starting, the DVR automatically records the program for the length of time indicated by the EPG.
While in theory the example described above should work perfectly, in practice errors may occur. For example, the clock in the recording device or server might not be perfectly accurate, or might not be synchronized with the clock utilized by the broadcaster. In addition, the program might start early or late, or run past the scheduled end time. Frequently, a program's start time will vary; sometimes the program will start on time, while other times the program will start late. For example, a sports program shown before the specified program might occasionally delay the program's start time by a variable amount.
Often, for whatever reason, the recording device simply starts recording a few seconds after the start of the program. Certain programs contain interesting material at the very beginning (such as the chalkboard scene in “The Simpson's”) and the user may be annoyed to find that the recording device failed to record such material.
Accordingly, there is a need in the art for a way to record programs that does not suffer from the deficiencies described above.